Preparation and synthetic application of {alpha}-phenylthioethylsamarium compound
- Kyoto Univ. (Japan)
Although samarium(II) iodide-mediated reaction of organohalides with carbonyl compounds has been applied to various organic syntheses, intermediary organosamarium species could be detected only when HMPA exists in the reaction system. The authors now report the detection of {alpha}-phenylthioethylsamarium compound in the absence of HMPA and application to diastereoselective reaction with aldehydes. A treatment of the organosamarium reagent, prepared from 1-chloroethyl phenyl sulfide and samarium(II) iodide, with D{sub 2}O afforded 1-deuterioethyl phenyl sulfide in 53% yield (82% D). The reagent reacted with aldehyde containing a stereogenic center at {alpha}-position to give {beta}-hydroxysulfide with high diastereoselectivity. Reaction using Barbier type procedure afforded the same results. These results suggest that {alpha}-phenylthioethylsamarium species is also generated in the Barbier type reaction. Configurational stability of {alpha}-thiosubstituted alkylmetal compounds seems to depend on the applied metal. Hoffmann Test indicated that the configuration of {alpha}-phenylthloethylsamarium compound is unchanged during the reaction with aldehyde, while that of {alpha}-alkylthioalkyllithium is unstable.
- OSTI ID:
- 250127
- Report Number(s):
- CONF-9508100--
- Country of Publication:
- United States
- Language:
- English
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